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<h1 class="title">imagecomposer.cpp 示例文件</h1>
<span class="subtitle">painting/imagecomposition/imagecomposer.cpp</span>
<!-- $$$painting/imagecomposition/imagecomposer.cpp-description -->
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<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
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  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
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  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
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  <span class="preprocessor">#include &quot;imagecomposer.h&quot;</span>

  <span class="preprocessor">#include &lt;QtWidgets&gt;</span>

  <span class="keyword">static</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qsize.html">QSize</a></span> resultSize(<span class="number">200</span><span class="operator">,</span> <span class="number">200</span>);

  ImageComposer<span class="operator">::</span>ImageComposer()
  {
      sourceButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qtoolbutton.html">QToolButton</a></span>;
      sourceButton<span class="operator">-</span><span class="operator">&gt;</span>setIconSize(resultSize);

      operatorComboBox <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qcombobox.html">QComboBox</a></span>;
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceOver<span class="operator">,</span> tr(<span class="string">&quot;SourceOver&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_DestinationOver<span class="operator">,</span> tr(<span class="string">&quot;DestinationOver&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Clear<span class="operator">,</span> tr(<span class="string">&quot;Clear&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Source<span class="operator">,</span> tr(<span class="string">&quot;Source&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Destination<span class="operator">,</span> tr(<span class="string">&quot;Destination&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceIn<span class="operator">,</span> tr(<span class="string">&quot;SourceIn&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_DestinationIn<span class="operator">,</span> tr(<span class="string">&quot;DestinationIn&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceOut<span class="operator">,</span> tr(<span class="string">&quot;SourceOut&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_DestinationOut<span class="operator">,</span> tr(<span class="string">&quot;DestinationOut&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceAtop<span class="operator">,</span> tr(<span class="string">&quot;SourceAtop&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_DestinationAtop<span class="operator">,</span> tr(<span class="string">&quot;DestinationAtop&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Xor<span class="operator">,</span> tr(<span class="string">&quot;Xor&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Plus<span class="operator">,</span> tr(<span class="string">&quot;Plus&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Multiply<span class="operator">,</span> tr(<span class="string">&quot;Multiply&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Screen<span class="operator">,</span> tr(<span class="string">&quot;Screen&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Overlay<span class="operator">,</span> tr(<span class="string">&quot;Overlay&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Darken<span class="operator">,</span> tr(<span class="string">&quot;Darken&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Lighten<span class="operator">,</span> tr(<span class="string">&quot;Lighten&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_ColorDodge<span class="operator">,</span> tr(<span class="string">&quot;ColorDodge&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_ColorBurn<span class="operator">,</span> tr(<span class="string">&quot;ColorBurn&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_HardLight<span class="operator">,</span> tr(<span class="string">&quot;HardLight&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SoftLight<span class="operator">,</span> tr(<span class="string">&quot;SoftLight&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Difference<span class="operator">,</span> tr(<span class="string">&quot;Difference&quot;</span>));
      addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Exclusion<span class="operator">,</span> tr(<span class="string">&quot;Exclusion&quot;</span>));

      destinationButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qtoolbutton.html">QToolButton</a></span>;
      destinationButton<span class="operator">-</span><span class="operator">&gt;</span>setIconSize(resultSize);

      equalLabel <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(tr(<span class="string">&quot;=&quot;</span>));

      resultLabel <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>;
      resultLabel<span class="operator">-</span><span class="operator">&gt;</span>setMinimumWidth(resultSize<span class="operator">.</span>width());

      connect(sourceButton<span class="operator">,</span> SIGNAL(clicked())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(chooseSource()));
      connect(operatorComboBox<span class="operator">,</span> SIGNAL(activated(<span class="type">int</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(recalculateResult()));
      connect(destinationButton<span class="operator">,</span> SIGNAL(clicked())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(chooseDestination()));

      <span class="type"><a href="qgridlayout.html">QGridLayout</a></span> <span class="operator">*</span>mainLayout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgridlayout.html">QGridLayout</a></span>;
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(sourceButton<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">3</span><span class="operator">,</span> <span class="number">1</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(operatorComboBox<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(destinationButton<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">2</span><span class="operator">,</span> <span class="number">3</span><span class="operator">,</span> <span class="number">1</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(equalLabel<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">3</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(resultLabel<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">4</span><span class="operator">,</span> <span class="number">3</span><span class="operator">,</span> <span class="number">1</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>setSizeConstraint(<span class="type"><a href="qlayout.html">QLayout</a></span><span class="operator">::</span>SetFixedSize);
      setLayout(mainLayout);

      resultImage <span class="operator">=</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span>(resultSize<span class="operator">,</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span><span class="operator">::</span>Format_ARGB32_Premultiplied);

      loadImage(<span class="string">&quot;:/images/butterfly.png&quot;</span><span class="operator">,</span> <span class="operator">&amp;</span>sourceImage<span class="operator">,</span> sourceButton);
      loadImage(<span class="string">&quot;:/images/checker.png&quot;</span><span class="operator">,</span> <span class="operator">&amp;</span>destinationImage<span class="operator">,</span> destinationButton);

      setWindowTitle(tr(<span class="string">&quot;Image Composition&quot;</span>));
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>chooseSource()
  {
      chooseImage(tr(<span class="string">&quot;Choose Source Image&quot;</span>)<span class="operator">,</span> <span class="operator">&amp;</span>sourceImage<span class="operator">,</span> sourceButton);
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>chooseDestination()
  {
      chooseImage(tr(<span class="string">&quot;Choose Destination Image&quot;</span>)<span class="operator">,</span> <span class="operator">&amp;</span>destinationImage<span class="operator">,</span> destinationButton);
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>recalculateResult()
  {
      <span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode mode <span class="operator">=</span> currentMode();

      <span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span> painter(<span class="operator">&amp;</span>resultImage);
      painter<span class="operator">.</span>setCompositionMode(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Source);
      painter<span class="operator">.</span>fillRect(resultImage<span class="operator">.</span>rect()<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>transparent);
      painter<span class="operator">.</span>setCompositionMode(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceOver);
      painter<span class="operator">.</span>drawImage(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> destinationImage);
      painter<span class="operator">.</span>setCompositionMode(mode);
      painter<span class="operator">.</span>drawImage(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> sourceImage);
      painter<span class="operator">.</span>setCompositionMode(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_DestinationOver);
      painter<span class="operator">.</span>fillRect(resultImage<span class="operator">.</span>rect()<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>white);
      painter<span class="operator">.</span>end();

      resultLabel<span class="operator">-</span><span class="operator">&gt;</span>setPixmap(<span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span><span class="operator">::</span>fromImage(resultImage));
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>addOp(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode mode<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>name)
  {
      operatorComboBox<span class="operator">-</span><span class="operator">&gt;</span>addItem(name<span class="operator">,</span> mode);
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>chooseImage(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>title<span class="operator">,</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span> <span class="operator">*</span>image<span class="operator">,</span>
                                  <span class="type"><a href="qtoolbutton.html">QToolButton</a></span> <span class="operator">*</span>button)
  {
      <span class="type"><a href="../qtcore/qstring.html">QString</a></span> fileName <span class="operator">=</span> <span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>getOpenFileName(<span class="keyword">this</span><span class="operator">,</span> title);
      <span class="keyword">if</span> (<span class="operator">!</span>fileName<span class="operator">.</span>isEmpty())
          loadImage(fileName<span class="operator">,</span> image<span class="operator">,</span> button);
  }

  <span class="type">void</span> ImageComposer<span class="operator">::</span>loadImage(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>fileName<span class="operator">,</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span> <span class="operator">*</span>image<span class="operator">,</span>
                                <span class="type"><a href="qtoolbutton.html">QToolButton</a></span> <span class="operator">*</span>button)
  {
      image<span class="operator">-</span><span class="operator">&gt;</span>load(fileName);

      <span class="comment">// Scale the image to given size</span>
      <span class="operator">*</span>image <span class="operator">=</span> image<span class="operator">-</span><span class="operator">&gt;</span>scaled(resultSize<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>KeepAspectRatio);

      <span class="type"><a href="../qtgui/qimage.html">QImage</a></span> fixedImage(resultSize<span class="operator">,</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span><span class="operator">::</span>Format_ARGB32_Premultiplied);
      <span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span> painter(<span class="operator">&amp;</span>fixedImage);
      painter<span class="operator">.</span>setCompositionMode(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_Source);
      painter<span class="operator">.</span>fillRect(fixedImage<span class="operator">.</span>rect()<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>transparent);
      painter<span class="operator">.</span>setCompositionMode(<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode_SourceOver);
      painter<span class="operator">.</span>drawImage(imagePos(<span class="operator">*</span>image)<span class="operator">,</span> <span class="operator">*</span>image);
      painter<span class="operator">.</span>end();
      button<span class="operator">-</span><span class="operator">&gt;</span>setIcon(<span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span><span class="operator">::</span>fromImage(fixedImage));

      <span class="operator">*</span>image <span class="operator">=</span> fixedImage;

      recalculateResult();
  }

  <span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode ImageComposer<span class="operator">::</span>currentMode() <span class="keyword">const</span>
  {
      <span class="keyword">return</span> (<span class="type"><a href="../qtgui/qpainter.html">QPainter</a></span><span class="operator">::</span>CompositionMode)
             operatorComboBox<span class="operator">-</span><span class="operator">&gt;</span>itemData(operatorComboBox<span class="operator">-</span><span class="operator">&gt;</span>currentIndex())<span class="operator">.</span>toInt();
  }

  <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span> ImageComposer<span class="operator">::</span>imagePos(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qimage.html">QImage</a></span> <span class="operator">&amp;</span>image) <span class="keyword">const</span>
  {
      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qpoint.html">QPoint</a></span>((resultSize<span class="operator">.</span>width() <span class="operator">-</span> image<span class="operator">.</span>width()) <span class="operator">/</span> <span class="number">2</span><span class="operator">,</span>
                    (resultSize<span class="operator">.</span>height() <span class="operator">-</span> image<span class="operator">.</span>height()) <span class="operator">/</span> <span class="number">2</span>);
  }

</pre>
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<!-- @@@painting/imagecomposition/imagecomposer.cpp -->
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